This document provides configuration information for Cisco routers connected back-to-back using Frame Relay (FR) encapsulation with the Local Management Interface (LMI) enabled. The routers are connected using data communication equipment (DCE) and a data terminal equipment (DTE) serial cable. One of the routers is configured to serve as a hybrid FR switch to respond to LMI status enq sent by the second router. The router connected to the DCE cable must provide clocking.

In this configuration, Router1 provides the clock at 64 kbps (clock rate 64000). Back-to-back setup is useful in test environments. Such a configuration is necessary only if the LMI debug messages are to be checked.

For information on the most common method used to configure routers back-to-back with FR encapsulation, please refer to Back-to-Back Frame Relay.

This configuration was developed and tested using the software and hardware versions below.

Cisco IOS Software Release 12.2(10b).

Cisco 2500 series routers.

The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.

Router1 is configured to function as a hybrid Frame Relay switch and respond to LMI enquires sent by Router 2. The global command frame-relay switching enables permanent virtual circuit (PVC) switching on Router1. The interface command frame-relay intf-type dce enables Router1 to function as a switch connected to a router. The no keepalive command has not been added to either router. No special configuration is needed for Router2.

For more information on configuring a router as a hybrid DTE/DCE FR switch, please see the configuration example in Hybrid Frame Relay Switching.

The show frame-relay pvc command used for Router1 provides the status of PVCs and confirms that map statements are configured properly. Router1 acts as a Frame Relay DCE device (FR switch).

If you have the output of a show frame-relay pvc command from your Cisco device, you can use to display potential issues and fixes. To use , you must be a registered customer, be logged in, and have JavaScript enabled.

You can use Output Interpreter to display potential issues and fixes. To use Output Interpreter, you must be a
registered customer, be logged in, and have JavaScript enabled.

The output from the show frame-relay lmi command confirms the role of Router1 as a FR DCE device (FR switch). The output shows Router1 receiving status enquiries from Router2 and also shows Router1 returning status messages to Router 2.

If you have the output of a show frame-relay lmi command from your Cisco device, you can use to display potential issues and fixes. To use , you must be a registered customer, be logged in, and have JavaScript enabled.

You can use Output Interpreter to display potential issues and fixes. To use Output Interpreter, you must be a
registered customer, be logged in, and have JavaScript enabled.

Output from the debug frame-relay lmi command on Router2 shows partial LMI status reports are being received every ten seconds. Router1 sends full LMI status reports to Router2 every 60 seconds. The debug frame-relay lmi command displays information on the LMI packets exchanged between the router and the FR service provider.